1. Field of the Invention
The present invention relates to an air-mat apparatus which make use of pressurized air to relieve elderly people, who have been long in bed, from bedsores.
2. Description of the Related Art
As is shown in FIG. 1, the conventional air-mat apparatus of such a type comprises air pump 30 for supplying pressurized air, an air mat 36, solenoid valves 34 connecting the air mat 36 to pump 30, and control circuit 35 for controlling solenoid valves 34. The air mat 36 comprises elongated air bags 31 arranged parallel to one another, and a zigzag air bag 32 having holes 32'. Zigzag air bag 32 is connected one of solenoid valves 34, and air bags 31 are connected to the remaining solenoid valves 34, respectively. Valves 34 are connected to air pump 30.
In operation, control circuit 35 controls solenoid valves 34, thus supplying the pressurized air from air pump 30 to air bags 31 and zigzag air bag 32, such that any two adjacent air bags 31 are alternately inflated, and the air is jetted outward through holes 32' of zigzag air bag 32. As air bags 32 are repeatedly inflated and deflated, they message the occupant of the air mat. Further, the air jetted outward through holes 32' of zigzag air bag 32 dries the clothes which the occupant wears, thus keeping the occupant's skin moderately dry.
Solenoid valves 34, however, cannot be controlled so precisely as to supply the pressurized air to the air mat 36 at a rate optimum to the physical conditions of the occupant of the air mat. The conventional air-mat apparatus is inevitably unable to relieve the occupant completely from bedsores. In particular, it is difficult with the conventional apparatus to adjust the supply of air to zigzag air bag 32 so as to maintain the occupant's skin properly dry.